Open source system call tests.

PiperOrigin-RevId: 224886231
Change-Id: I0fccb4d994601739d8b16b1d4e6b31f40297fb22

1 files changed, 170 insertions, 0 deletions

diff --git a/test/syscalls/linux/access.cc b/test/syscalls/linux/access.cc
new file mode 100644
index 000000000..6ea070a5d
--- /dev/null
+++ b/test/syscalls/linux/access.cc
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+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "gtest/gtest.h"
+#include "test/util/capability_util.h"
+#include "test/util/fs_util.h"
+#include "test/util/temp_path.h"
+#include "test/util/test_util.h"
+
+using ::testing::Ge;
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+class AccessTest : public ::testing::Test {
+ public:
+  std::string CreateTempFile(int perm) {
+    const std::string path = NewTempAbsPath();
+    const int fd = open(path.c_str(), O_CREAT | O_RDONLY, perm);
+    TEST_PCHECK(fd > 0);
+    TEST_PCHECK(close(fd) == 0);
+    return path;
+  }
+
+ protected:
+  // SetUp creates various configurations of files.
+  void SetUp() override {
+    // Move to the temporary directory. This allows us to reason more easily
+    // about absolute and relative paths.
+    ASSERT_THAT(chdir(GetAbsoluteTestTmpdir().c_str()), SyscallSucceeds());
+
+    // Create an empty file, standard permissions.
+    relfile_ = NewTempRelPath();
+    int fd;
+    ASSERT_THAT(fd = open(relfile_.c_str(), O_CREAT | O_TRUNC, 0644),
+                SyscallSucceedsWithValue(Ge(0)));
+    ASSERT_THAT(close(fd), SyscallSucceeds());
+    absfile_ = GetAbsoluteTestTmpdir() + "/" + relfile_;
+
+    // Create an empty directory, no writable permissions.
+    absdir_ = NewTempAbsPath();
+    reldir_ = JoinPath(Basename(absdir_), "");
+    ASSERT_THAT(mkdir(reldir_.c_str(), 0555), SyscallSucceeds());
+
+    // This file doesn't exist.
+    relnone_ = NewTempRelPath();
+    absnone_ = GetAbsoluteTestTmpdir() + "/" + relnone_;
+  }
+
+  // TearDown unlinks created files.
+  void TearDown() override {
+    ASSERT_THAT(unlink(absfile_.c_str()), SyscallSucceeds());
+    ASSERT_THAT(rmdir(absdir_.c_str()), SyscallSucceeds());
+  }
+
+  std::string relfile_;
+  std::string reldir_;
+
+  std::string absfile_;
+  std::string absdir_;
+
+  std::string relnone_;
+  std::string absnone_;
+};
+
+TEST_F(AccessTest, RelativeFile) {
+  EXPECT_THAT(access(relfile_.c_str(), R_OK), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, RelativeDir) {
+  EXPECT_THAT(access(reldir_.c_str(), R_OK | X_OK), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, AbsFile) {
+  EXPECT_THAT(access(absfile_.c_str(), R_OK), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, AbsDir) {
+  EXPECT_THAT(access(absdir_.c_str(), R_OK | X_OK), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, RelDoesNotExist) {
+  EXPECT_THAT(access(relnone_.c_str(), R_OK), SyscallFailsWithErrno(ENOENT));
+}
+
+TEST_F(AccessTest, AbsDoesNotExist) {
+  EXPECT_THAT(access(absnone_.c_str(), R_OK), SyscallFailsWithErrno(ENOENT));
+}
+
+TEST_F(AccessTest, InvalidMode) {
+  EXPECT_THAT(access(relfile_.c_str(), 0xffffffff),
+              SyscallFailsWithErrno(EINVAL));
+}
+
+TEST_F(AccessTest, NoPerms) {
+  // Drop capabilities that allow us to override permissions. We must drop
+  // PERMITTED because access() checks those instead of EFFECTIVE.
+  ASSERT_NO_ERRNO(DropPermittedCapability(CAP_DAC_OVERRIDE));
+  ASSERT_NO_ERRNO(DropPermittedCapability(CAP_DAC_READ_SEARCH));
+
+  EXPECT_THAT(access(absdir_.c_str(), W_OK), SyscallFailsWithErrno(EACCES));
+}
+
+TEST_F(AccessTest, InvalidName) {
+  EXPECT_THAT(access(reinterpret_cast<char*>(0x1234), W_OK),
+              SyscallFailsWithErrno(EFAULT));
+}
+
+TEST_F(AccessTest, UsrReadOnly) {
+  // Drop capabilities that allow us to override permissions. We must drop
+  // PERMITTED because access() checks those instead of EFFECTIVE.
+  ASSERT_NO_ERRNO(DropPermittedCapability(CAP_DAC_OVERRIDE));
+  ASSERT_NO_ERRNO(DropPermittedCapability(CAP_DAC_READ_SEARCH));
+
+  const std::string filename = CreateTempFile(0400);
+  EXPECT_THAT(access(filename.c_str(), R_OK), SyscallSucceeds());
+  EXPECT_THAT(access(filename.c_str(), W_OK), SyscallFailsWithErrno(EACCES));
+  EXPECT_THAT(access(filename.c_str(), X_OK), SyscallFailsWithErrno(EACCES));
+  EXPECT_THAT(unlink(filename.c_str()), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, UsrReadExec) {
+  // Drop capabilities that allow us to override permissions. We must drop
+  // PERMITTED because access() checks those instead of EFFECTIVE.
+  ASSERT_NO_ERRNO(DropPermittedCapability(CAP_DAC_OVERRIDE));
+  ASSERT_NO_ERRNO(DropPermittedCapability(CAP_DAC_READ_SEARCH));
+
+  const std::string filename = CreateTempFile(0500);
+  EXPECT_THAT(access(filename.c_str(), R_OK | X_OK), SyscallSucceeds());
+  EXPECT_THAT(access(filename.c_str(), W_OK), SyscallFailsWithErrno(EACCES));
+  EXPECT_THAT(unlink(filename.c_str()), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, UsrReadWrite) {
+  const std::string filename = CreateTempFile(0600);
+  EXPECT_THAT(access(filename.c_str(), R_OK | W_OK), SyscallSucceeds());
+  EXPECT_THAT(access(filename.c_str(), X_OK), SyscallFailsWithErrno(EACCES));
+  EXPECT_THAT(unlink(filename.c_str()), SyscallSucceeds());
+}
+
+TEST_F(AccessTest, UsrReadWriteExec) {
+  const std::string filename = CreateTempFile(0700);
+  EXPECT_THAT(access(filename.c_str(), R_OK | W_OK | X_OK), SyscallSucceeds());
+  EXPECT_THAT(unlink(filename.c_str()), SyscallSucceeds());
+}
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor